Design and modeling of synthetic test circuit to generate four parameter TRV envelope

Short circuit current and transient recovery voltage arising in power systems under fault conditions can develop thermal and dielectric failures in the system and may create severe damage to the critical components. Therefore, main devices in our power system especially like circuit breaker extremely need to be tested first. Testing can be done by two ways; direct testing, and synthetic testing. For testing high voltage circuit breakers, direct testing is not economical because of high power generating capability requirement of laboratory, high installation cost, and more space. Synthetic testing is an economical method for testing of high voltage circuit breakers. In synthetic test circuit, it is quite complex to choose the circuit components value for a desired transient recovery voltage (TRV) envelope. It is because, modification of any component value may cause change in all parameters of output waveform. This paper proposes a synthesis process to design synthetic test circuit to generate four-parameter transient recovery voltage (TRV) envelope for circuit breaker testing. A synthetic test circuit has been simulated in PSCAD to generate four-parameter TRV envelope for 145kV rating of circuit breaker.